Retrievable well apparatus



Jan. 22, 1957 R g, BAKER ,?7&43@

RETRIEVABLE WELL APPARATUS Filed 00i. 4. 1954 2 Sheets-Sheet 1 INV EN TOR.

EUBEN 6.

ATTORNEY:

R. C BAKER RETRIEVABLE WELL APPARATUS 2 Sheet 5 2 Filed Oct. 4, 1954 Q Mg m J NK 0 MA w MB 4 f if M United States Patent 2,778,430 RETRIEVABLE WELL APPARATUS Reuben .C. Baker, Coalinga, Calif assignor to Baker Oil 7f1ools, Inc Los Angeles, Calif a corporation of Cairorma Application 0ctober 4, 1954, Serial No. 460,117 8Claims. (Cl. 166-139) The present invention relates to subsurface well apparatus, and more particularly to apparatus adapted to be anchored'in a well casing, or similar conduit, disposed in a well bore.

Certain types of subsurface well tools are operated by manipulating the tubular running-in strings to which the tools are attached, movement of parts of the tools being resisted or prevented by members that frictionally or positively engage the walls of well conduits or open holes in which the 'tools are disposed. After the particular tool has'performed its purposes in the well bore, its removal can be expedited and facilitated by holding the section of the tubular string of drill pipe or tubing above the rotary table stationary and rotating the tubular string portion remaining --in the well "bore. However desirable rotation of the tubular string within the hole may be, it possesses the undesirable feature of rotating the well tool and its members that engage the wall of the well conduit or open hole, dragging such members around the wall, with potential damage to them and the other parts of the tool to which the members are connected.

Accordingly, it is an object of the present invention to provide an improved subsurface well tool apparatus emhodying members engaging the wall of the hole or conduit string, in which such members are rotationally disconnected from the remainder of the well tool apparatus when the latter is to be removed from the well bore, thereby allowing the tubular string to which the apparatus is connected to be rotated without correspondingly rotating the wall engaging members.

Another object of the invention is to provide an apparatus of the character indicated, embodying-a simplified mechanism for initially securing the wall engaging members to the remainder of the apparatus, to enable proper manipulation and operation of the apparatus, and for obtaining their rotational detachment from the remainder of the apparatus, when desired.

This invention possessewtnany other advantages, and has other objects which maybe made more clearly apparent from a consideration'of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but itis to be understood that such detailed description isnot to be taken in a limiting sense, since the scope. of the invention is best defined by the appended claims.

Referring to the drawings:

Figure 1 is a side elevation of a well packer embodying the invention;

Fig. .2 is a longitudinal section, on an enlarged scale, through the well packer shown in Fig. l, with the packer parts-disclosed in retracted position;

Fig. 3 is a view similar to Fig. 2, :showingthe well packerparts expanded against the wellcasing;

Fig. 4 is a fragmentary longitudinal section diselosing :the-frictiondrag portion of the apparatuszrotationallydisconnected from the remainder of:the.:appara "ice Fig. 5 is a cross'section taken along the line 5-5 on Fig.

The well packer A disclosed in the drawings is of the type adapted to be run in a well casing B on a string of tubing C, to be anchored in packed-01f condition in the well casing, preferably against downward movement therewithin. The well packer also embodies a control valve portion for determining the flow of fluid between the interior of the tubular string C and packer A and the annulus D above .the packer between the tubular string C and the well casing B.

The well packer includes a central tubular body or mandrel 10, which is disclosed as consisting of an upper section 11 suitably secured to a lower section 12, as through the use of welding material 13. The upper section has a threaded box 14 for the reception of a threaded pin 15 at the lower end of an adjacent section of the tubular string C. The body 10 extends throughout the entire length of the well packer device, and may have tubular tailpipe, or other tubing, (not shown) connected to its lower end 16, for extension to a predeterimned lower lo cation in the well casing. Any tubing depending from the body should not have an outside diameter that is greater than the outside diameter of the body 10 itself.

A plurality of slips 17 is provided to anchor the body 10 to the well casing against downward movement therewithin. These slips have external wickers 18 facing predominantly in a downward direction, to dig into the wall of the well casing B and preclude their downward move ment. The slips 17 are urged in a radial outward direction, and also in a radial inward direction, by a tapered expander 1) slidable relatively on the body and disposed within the slips. This expander has downward and inwardly tapering surfaces 20 engageable with companion surfaces 21 on the slips, for the purpose of expanding the slips in an outward direction whenever the slips and expander move longitudinally toward ecah other. Each slip 17 has a positive connection with the expander 19, to secure retraction of the slips when the expander and slips move in longitudinal directions away from each other. As disclosed, such positive connection is effected by providing tongues 22 on the opposed sides of the inner portions of each slip slidable in opposed companion grooves 23 in the expander.

In addition to anchoring the body 10 to the well casing B, it is desired to elfect an annular seal between the body and .the well casing. Such seal canbe provided by a packing structure 24. As disclosed in the drawings, this structure includes a rubber, or rubber-like, packing sleeve 25 surrounding the body 10 and having its upper and lower ends 26, 2.7 piloted within upper and lower rings 28, 29 to which the upper and lower ends of the packing are permanently secured by a molding operation. The lower ring 29 is threaded into a lower gauge ring 30 which is, in turn, threaded onto the upper end of the tapered expander 19; whereas the upper ring 28 is threaded into an upper gauge ring 31 which is, in turn, threaded onto the lower end of an upper valve head and packing actuating member 32 surrounding the body 10.

The upper portion of this valve head member 32 is provided with a countcrbore 33, the lower portion 34 of which forms an axial seat for a seal ring 35 contained in a groove 36 in a head 37 extending outwardly from the upper body section 11. The wall 38 of the counterbore forms a cylindrical seat for the reception of the periphery of the flange or head 37, and for sealing engagement with a side seal 39, in the form of a rubber, or

'rubber'likc, O ring confined .with a groove 40 in the periphery of'the flange 31. When the flange 37 is in an up- -wardposition out of its seat 38, generally radial ports 41 'ex-tendingthrough'the body ltlafiord communicatiombe- -tween the-interior of the body and the exterior of the body above the valve head member 32. When the body '10 is moved downwardly in the valve head member 32,

so as to engage the seal rings 35, 39 with their companion seats, 34, 38, then the passages through the ports 41 are closed.

The upper bodyv section 11 is releasably connected to the valve head and packing actuating member 32 by means of an upper safety joint. Thus, the upper section 11 has external left-hand threads 42 engaging internal left-hand threads 43 in a threaded sleeve 44 disposed within an enlarged bore 45 in the lower portion of the valve head member 32. A longitudinally extending key 46 is welded, or otherwise suitably secured; to the exterior of the safety sleeve 44, and this key is slidable in a companion keyway 47 formed in the valve head member 32. The lower end of the sleeve 44 is initially spaced a substantial distance above a bridge ring 48, which engages the upper end of the packing sleeve 25, and which extends between the periphery of the body or mandrel and the lower portion of the valve head member 32, so as to prevent the packing sleeve from moving upwardly into the lower counterbore of the member:32. This ring 48 ispreeluded from moving upwardly with respect to the valve head member 32 by engaging a suitable shoulder 49 therein.

The slips 17 are all connected together for joint longitudinal movement. Thus, each slip has a pin 50 connected to the upper end of a link 51 that has its lower end provided with a radial hole 52 loosely receiving a radial pin 53 secured to a slip ring 54 attached to the 5 upper end of a ratchet collar 55 forming the outer portion of a releasable lock or latch device that controls the operationof the well packer. The slip ring 54 may be secured to the collar 55 by one or more screws 56. As shown in the drawings, this collar surrounds the lower portion of a ratchet sleeve 57 having longitudinally spaced circumferential ratchet teeth 58 facing in a downward di r'ection, the upper end of this sleeve having an internal key extends radimly and engages one end 64 of an expansible and contractible split ratchet sleeve 65 disposed within the ratchet collar 55, this sleeve possessing internal teeth 66 facing in an upward direction and adapted to mesh with the external ratchet teeth 58 on the ratchet sleeve 57. The other end 67 of the sleeve 65 is engageable with a key or stop 68 securedgovithin a groove 69; in the ratchet collar 55. The exterior of thesplit ratchet sleeve 65 is provided with longitudinally spaced circumferential cam teeth 70 having cam surfaces 71 tapering in a downward and inward direction and engageable with companion longitudinally spaced cam teeth 72 in the collar having surfaces 73 also tapering in a downward and inward direction. The split ratchet sleeve 65 normally contracts to place its ratchet teeth 66 in engagement with the 'sleeve ratchet teeth 58. When this occurs, the body 10 is connected to the collar 55 and cannotmove downwardly with respect thereto, although the body 10 can ratchetfreely up through the ratchet sleeve 65. Any tendency for the ratchet sleeve 65 to disconnect from the body 10 is prevented by the coengagement of the cam teeth 70, 72,

which urge the ring or sleeve 65 in an inward direction.

When it is desired to move the'body 10 in a downward direction with respect to the ratchet collar 55,- for the purpose of expanding the slips 17 and the packing sleeve 25 outwardly against the well casing B, the tubular string C and the body 10 connected thereto are turnedto the right,

or in a clockwise direction, asseen from the top of the well'hole, and when'the ratchet collar 55 is prevented from rotation, as-described hereinbelow, such turning causes a corresponding turning of the ratchet sleeve 57 and of the key 63, the key engaging one end 64 of the split ratchet sleeve member 65. Since its other end cannot move through engaging thestationary stop 68, the sleeve 65 is expanded to bring its teeth 66 out of engagement with the ratchet sleeve teeth 58. This then allows the body 10 to be lowered within the ratchet collar 55.

Rotation of the ratchet collar 55 is prevented whenever a friction drag device 75, or corresponding conduit engageable, means, is connected thereto. This friction drag device includes a lower collar 79a of a known type slidable on the lower -body section 12 and having the lower ends of circumferentially spaced outwardly bowed springs 79 welded or otherwise suitably attached thereto. The upper ends of the springs are welded to an upper ring 81 secured to an upper friction brake collar 82, as by use of the screws 83, the collar 82 constituting part of the friction drag device. This upper collar 82 is threadedly secured by a left-hand threaded connection 90 to the lower skirt portion 84 of the ratchet collar 55, the left-hand threaded interconnection being adapted for detachment, in the manner described hereinbelow, to enable the friction drag device to be rotationally disconnected from the ratchet collar 55 and the remainder of the apparatus, when the latter is to be withdrawn to the top of the well bore.

Unthreading between the ratchet collar 55 and the upper drag collar 82 is resisted-by a friction brake provided between these collars. As specifically disclosed, a plurality of spring fingers 91 are integral with and extend upwardly from the main portion of the upper collar 82, the inner surface of these spring fingers frictionally engaging the periphery of the friction brake portion 92 of .the ratchet collar 55. Specifically, the brake fingers 91 may be provided by cutting longitudinal slots 93 in the relatively thin wall of the upper portion of the upper. collar 82. The fingers 91 inherently tend to contractzagainst the periphery of the friction brake portion 92 of the collar, and thereby tend' to prevent relative motion'ibetween the ratchet collar 55 and the upper collar 82: 1 r

In assembling the apparatus, the upper drag collar 82 is threaded onto the lower-skirt portion 84 of the ratchet collar 55 by turning the upper drag collar to the left until the left-hand threads are substantially fully intereugaged. The extent of threading of the upper collar 82 onto the skirt 84 is limited by engagement of an upwardly extending projection 94 on one of the spring fingers with a'stop screw or pin 95 secured to the ratchet collar 55 and extending laterally therefrom above the upper ends of the other brake fingers 91. When the ratchet collar 55 is turned to the right, it will be shifted in a relative upward direction with respect to theupper drag collar 82, the left-hand thread on the ratchet collar feeding relatively upward out of the companion female thread in the drag collar 82. The pitch of the threaded connection is such that before the ratchet collar 55 has made substantially a complete revolution, the upward projection 94 on the spring finger is disposed below the pin 95, so as not to interfere with the continued rotation and unthreading of the ratchet collar 55 in an upward direction out of the upper drag collar 82. When the upprdrag collar 82 has been completely unthreaded from the ratchet collar, the former can move relatively downward along the body of the tool to an extent limited by engagement of the lower inwardly directed flange portion 96 of the upper drag collar with a stop and retrieving ring 97 disposed around the lower body member 12 and secured thereto, as by means of one or more screws 98.

-.The apparatus is run in the well casing with the parts in the position shown in Figs. 1 'and 2, in which the body ratchet sleeve 57 secured thereto.

10. and the ratchet sleeve 57 are in their uppermost position with respect to'the other parts, the safety sleeve 44 engaging theupper end or shoulder 92a of the counterbore 45, the seal rings 35, 39 being disposed ofi' their companion seats 34, 38, so as to open the ports 41. At this time, also, the packing sleeve 25 and slips 17 are in their retracted position. The upper collar 82 of the friction drag device 75 is fully threadedly engaging the skirt portion 84 of the ratchet collar 55, the brake fingers 91 frictionally engaging the cylindrical brake portion 92 of the ratchet collar, the upper extension 94- of one of the spring fingers having its side engaging the stop pin 95.

The apparatus is loweredth rough the well casing B, with the parts in the positions shown in Figs. 1 and 2, the split ratchet sleeve teeth 65 engaging the companion teeth 58 on the other member 57 to preclude relative downward movement of the body with respect to the other parts. When the location in the well casing B is reached at which the well packer A is to be anchored in packed-off condition, the tubular string C is turned to the right, such motion being transmitted to the packer body and the This turning motion also moves the key 63 arcuately, causing it to expand the split ratchet sleeve 65 and open it to a larger diameter, in which its internal teeth 66 are moved out of engagement with the ratchet sleeve teeth 58. This relative turning movement can occur since the ratchet collar 55 is prevented from turning by virtue of the engagement between the friction brake elements 92, 91, which effectively couple the ratchet collar 55 to the upper drag collar 82, and because of the fact that the outwardly bowed springs 7 secured to the upper drag collar are friction ally engaging the wall of the well casing. A lesser torque is required to expand the ratchet sleeve 65 and disengage its internal teeth 66 from the ratchet sleeve teeth 58 than is required to cause the'ratchet collar 55 to slip within the friction brake fingers 91. The extent of frictional engagement between the friction brake fingers 91' and the. brake portion 92 of the ratchet collar, however, is substantially less than the friction force of engagement of the outwardly bowed springs 79 with the wall of the well cas ing B.

With the split ratchet sleeve 65 in its unclutched or uncoupled position, the tubular spring C is shifted in the downward direction, to correspondingly shift the body It) in a downward direction. The parts externally of the body 10 and the ratchet sleeve 57 secured thereto cannot move in a downward longitudinal direction since such motion is resisted by the friction spring 72 of the drag device 75 engaging the wall of the well casing B. Accordingly, the body 10 moves downwardly freely, the key 63 not interfering with the downward movement in view of the longitudinal slot 62 in the ratchet sleeve. At first, the body 19 moves downwardly, to place the flange 37 within the counter-bore 33 of the upper head member 32 and to bring its seal 35, 39 into sealing engagement with the companion seats 34, 38, thereby closing the ports 41. Thereafter, the body 10 and valve head member 32 move downwardly together, the packing sleeve 25 .and expander 29 also being urged in a downward direction, to shift the expander 19 downwardly within the slips 17, which are prevented from moving downwardly by the friction springs 79. In this manner, the tapered expander 19 is forced down into the slips 17, urging the latter in a radial outward direction into anchoring engagement with the wall of the well casing B. 'When such engagement occurs, the tapered expander 19 cannot move downwardly any further, which then allows the upper head member 32 to be moved toward the tapered expander, foreshortening the packing sleeve 25 and expanding it radially outward into firm sealing engagement with the wall of the well casing and also with the periphery of the body 10. Thepacking material cannot move in an upward direction into the counterbore 45 of the head member 32 since the bridge ring 48 precludes this action from occurring.

The packer A is thus set in packed-oft" condition within 6 the well easing B, to. bridge the annulus D. between the body 10 of. the tool and; the well casing. The tool can then be used for any desired purpose. If it is desired to swab the well, then the swabbing of the tubular string C will produce a differential hydrostatic head in the annulus D between the tubular string and the casing. However, this head of fluid cannot displace the well packer A from its set condition because of the expanded packing sleeve 25, and of theslips 17, which are anchored against the casing B and resist downward movement of the tool therewithin. Whenever it is desired to equalize the hydrostatic head, it is merely necessary to move the tubular string C upwardly, for the purpose of pulling the flange 37 out of its companion seat 38 in the upper valve head member 32, thereby exposing the ports 41. After the hydrostatic head has been equalized, the tubular string C can again be moved downwardly, after first having partially turned the tubing string C and the packer body 10 to the right, for

the purpose of disconnecting the ratchet sleeve 57 fromthe split ratchet ring 65. Such upward and downward movement can occur as often as desired, without releasing the packing sleeve 25 and the slips 17 from the well casing B.

In the event it is desired to retrieve the well packer A from the well bore, it is merely necessary to move the tubular string C and the body 10 in an upward direction, the ratchet sleeve 57 ratcheting freely through the ratchet ring 65. When the safety sleeve ring 44 engages the shoulder 92 of the counterbore 45, it will transfer the upward movement of the body 10 to the upper head member 32, and this action will pull the head member away from the expander 19, allowing the packing sleeve 25 to retract. When fully retracted, the packing sleeve will then pull on the upper expander 19, in order to urge it in an upward direction away from the slips l7, and thereby retract the latter from the well casing B, in view of the tongue and groove connection 22, 23 therebetween. During this time, the drag springs 79 are tending to prevent upward movement of the slips 17. Following the retraction of the slips 17, the tubular string C is elevated, to elevate the entire Well packer A within and from the well casing, the friction drag springs 79 frictionally riding along the wall of the well casing.

As the tubing string C is elevated and withdrawn from the well casing, its joints are disconnected at the top of the well bore above the usual rotary table (not shown). It is desired to effect a disconnection between the joints of tubing above the rotary table and those within the well bore by rotating the table, in view of the time saving factor. However, it is not desired to rotate the drag springs 79 around the wall of the well casing B, which they frictionally engage, since they may be damaged or destroyed. In the present instance, the drag device is automatically disconnected from the remainder of the well packer merely as a result of rotating the tubing string C disposed within the well bore to the right. The rotation of the tubular string to the right is transmitted to the body 10 of the well packer, and from the body through the ratchet sleeve 57 to the key 63 secured to the end of the ratchet sleeve 65; The turning effort is transferred from the ratchet sleeve to the stop member 68 secured to the ratchet collar 55. By virtue of the mechanical interconnection between the parts just. described, the rotation of the tubing string C is transferred to the ratchet collar 55. Since the outwardly bowed drag springs 79 frictionally engage the wall of the Well casing B with a friction force that substantially exceeds the friction of the brake fingers 91 against the periphery of the ratchet collar 55 as well as the friction of the left-hand interengaging threads on the ratchet collar 55 andthe upper drag collar 82, the rotation of the ratchet collar 55 will result in a relative unthreading of its lower skirt portion 84 in a relative upward direction out of the upper drag collar 82. As described, above, before the first revolution has occurred, the stop pin 95 will have been elevated relatively above the upper end of the finger projection 94, to avoid interference with continued rotation and complete unscrewing of the ratchet collar 55 in an upward direction out of the drag collar 82.

When such complete unthreading disconnection has occurred, the drag collar 82 is fully disassociated rotationally from the ratchet collar 55, allowing the latter, as well as the remainder of the well packer parts and the tubing string C, to be rotated to the right without rotating the drag device 75 around and the wall of the well casing B. Accordingly, the entire apparatus is rotatable in the well bore with the exception of the drag device '75, to enable rapid disconnection of the joints of tubing to be made at the top of the hole. The tubing string C is elevated in the well casing, to re- 'trieve the well packer therewithin, and such elevating movement will also pull the friction drag device 75 upwardly with the other portions of the Well packer, in

view of the engagement of the retrieving ring 97 secured to the body with the lower end of the upper drag collar 82.

if, for some reason, the packing sleeve and the slips 17 cannot be retracted, for the purpose of removing the well packer from the well casing, the threaded safety joints 42, 43 and 59, 6G enable the tubing string C and the body 10, and any tubing depending from the body, to be removed. Thus, in the event the slips 17 are stucl: in the hole and cannot be freed, the tubular string C is rotated to the right. Since the parts eX- ternally of the packer body iii cannot rotate, being anchored to the well casing B, such rotation effects a shearing of the shear screw 61 connecting the ratchet sleeve 57 to the lower body section 12. Rotation of the body it) then produces a disconnection of the lower body section 12 from the ratchet sleeve 57 at their left- Thand threaded interconnection 59, 60. This same rotation of the body effects a disconnection of the upper body section 11 from the threaded sleeve 42, which is prevented from rotating by means of its key connection 46, 47 to the valve head member 32, that is precluded from turning, since the part connected thereto are anchored to the well casing B. The taking of a sufiicient number of turns on the tubular string C and the body 10 will effect complete unthreading of both external lefthand threads 42, as on the body from the corresponding internal left-hand threads 43, 59 on the threaded safety sleeve 44 and the ratchet sleeve 57, freeing the body it} from the remainder of the Well packer and enabling it to be elevated and withdrawn through the packer parts. Any tubing connected below the body can also be Withdrawn from the packer parts. Such withdrawing action is not interfered with by the ratchet key 63, since the latter only extends into the slot 63 in the sleeve 57, the latter remaining in the well casing.

The inventor claims:

l. In a well tool for use in a well conduit: a first member adapted for connection to a tubular string; a second member telescopically arranged with respect to said first member; means for transmitting the turning effort of said first member to said second member; conduit engageable means cooperable with said second member for resisting movement of said second member in said well conduit; means comprising a threaded connection between said conduit engageable means and second member for moving said conduit engageable means longitudinally of said members upon rotation of said first member and second member; and friction brake fingers on said conduit engageable means frictionally engaging said second member for resisting movement of said second member relative to said conduit engageable means.

2. In a Well tool for use in a well conduit: a first member adapted for connection to a tubular string; a second member telescopically arranged with respect to said first member; means for transmitting the turning efiort of said first member to said second member; conduit engageable means cooperable with said second member for resisting movement of said second member in said well conduit; means comprising a threaded connection between said conduit engageable means and second member for moving said conduit engageable means longitudinally of said members upon rotation of said first member and second member; and friction brake spring fingers secured to said conduit engageable means and disposed circumferentially around and frictionally engaging said second member to resist movement of said second member relative to said conduit engageable means.

3. In a well tool for use in a well conduit: a first member adapted for connection to a tubular running-in string; a second member telescopically arranged with respect to said first member; means for transmitting the turning efiort of said first member to said second member; a collar disposed around said second member; conduit engageable drag springs secured to said collar; a threaded connection between said collar and said second member for moving said collar longitudinally of said second member in response to rotation of said second member; and friction brake fingers secured to said collar and frictionally engaging second member.

4. In a well tool for use in a well conduit: a first member adapted for connection to a tubular running-in string; a second member telescopically arranged with respect to said first member; means for transmitting the turning effort of said first member to said second member; a collar disposed around said second member; conduit engageable drag springs secured to said collar; a threaded connection between said collar and said second member for moving said collar longitudinally of said second member in response to rotation of said second member; and friction brake spring fingers secured to said collar and disposed circumferentially around and frictionally engaging said second member to resist movement of said second member relative to said collar.

5. In a well tool for use in a well conduit: a part adapted for connection to a tubular string; a first member telescopically arranged with respect to said part; means for transmitting the turning effort of said part to said member; conduit engageable means for resisting movement of said member in said well conduit comprising a second member cooperable with said first member; means comprising a threaded connection between said members for moving said second member longitudinally of said first member upon rotation of said part and first member; and friction brake spring fingers on one of said members frictionally engaging said other member for resisting movement of said first member relative to said second member.

6. In a well tool for use in a Well conduit; a part adapted for connection to a tubular string; a first member telescopically arranged with respect to said part; means for transmitting the turning efiort of said part to said member; conduit engageable means for resisting movement of said member in said Well conduit comprising a second member cooperable with said first member; means com prising a threaded connection between said members for moving said second member longitudinally of said first member upon rotation of said part and first member; and friction brake spring fingers secured to one of said members and disposed circumferentially around and frictionally engaging said other member to resist movement of said first member relative to said second member.

7. In a well tool for use in a well conduit: a part adapted for connection to a tubular running-in string; a first member telescopically arranged with respect to said part; means for transmitting the turning effort of said part to said first member; a collar member disposed around said first member; conduit engageable drag springs secured to said collar member; a threaded connection between said collar member and said first member for moving said collar member longitudinally of said first member in response to rotation of said first member; and friction brake spring fingers secured to one of said members and disposed circumferentially around and frictionally engaging said other member to resist movement of said first member relative to said collar member.

8. In a well tool for use in a well conduit: a first member adapted for connection to a tubular running-in string; a second member telescopically arranged with respect to said first member; means for transmitting the turning efiort of said first member to said second member; a collar disposed around said second member; conduit engageable drag springs secured to said collar; a threaded connection between said collar and said second member for moving said collar longitudinally of said second member in response to rotation of said second member to completely unthread said second member from said collar; friction brake fingers secured to said collar and frictionally engaging said second member; and stop means on said first member engageable with said collar after unthreading of said collar from said second member to carry said collar and drag springs upwardly with said first member.

Bechaud Apr. 7, 1925 Lane Nov. 30, 1954 

